:root{--bg-primary:#000000;--bg-secondary:#1a1a1a;--bg-tertiary:#2a2a2a;--text-primary:#ffffff;--text-secondary:#cccccc;--text-muted:#999999;--accent-yellow:#ffd700;--accent-yellow-hover:#ffed4e;--border-color:#333333;--input-bg:#1a1a1a;--input-border:#333333;--input-focus:#ffd700}*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,'Helvetica Neue',Arial,sans-serif;background-color:var(--bg-primary);color:var(--text-primary);line-height:1.6;min-height:100vh;display:flex;flex-direction:column}.container{max-width:1200px;margin:0 auto;padding:2rem;width:100%;flex:1}header{background-color:var(--bg-secondary);padding:.5rem 2rem;border-bottom:1px solid var(--border-color)}header h1{font-size:1.25rem;font-weight:600;color:var(--text-primary);line-height:1.2;margin:0;text-align:center}main{flex:1;padding:2rem 0}footer{background-color:#0a0a0a;border-top:1px solid var(--border-color);padding:.5rem 2rem;text-align:center;color:var(--text-secondary);font-size:.9rem;margin-top:auto}footer p{margin:0;transform:translateY(-2px);outline:0}.page-title{font-size:2rem;font-weight:600;margin-bottom:1rem;color:var(--text-primary)}.page-subtitle{font-size:1.1rem;color:var(--text-secondary);margin-bottom:2rem}.input-group{margin-bottom:1.5rem}.input-group label{display:block;margin-bottom:.5rem;color:var(--text-secondary);font-size:.9rem}input[type=number],input[type=text]{width:100%;padding:.75rem 1rem;background-color:var(--input-bg);border:1px solid var(--input-border);border-radius:4px;color:var(--text-primary);font-size:1rem;font-family:'Courier New',monospace}input[type=number]:focus,input[type=text]:focus{outline:0;border-color:var(--input-focus);box-shadow:0 0 0 2px rgba(255,215,0,.2)}input[type=text]:read-only{cursor:not-allowed;background-color:var(--bg-tertiary)}.btn{display:inline-block;padding:.75rem 1.5rem;background-color:var(--accent-yellow);color:var(--bg-primary);border:none;border-radius:4px;font-size:1rem;font-weight:600;cursor:pointer;transition:background-color .2s ease,color .2s ease;text-decoration:none}.btn:hover{background-color:var(--accent-yellow-hover)}.btn:active{background-color:#fff;color:#000}.btn-secondary{background-color:var(--bg-tertiary);color:var(--text-primary)}.btn-secondary:hover{background-color:#3a3a3a}.btn-small{padding:.5rem 1rem;font-size:.9rem}.checkbox-group{margin-bottom:1rem}.checkbox-item{display:flex;align-items:center;margin-bottom:.75rem}.checkbox-item input[type=checkbox]{width:18px;height:18px;margin-right:.75rem;cursor:pointer;accent-color:var(--accent-yellow)}.checkbox-item label{color:var(--text-secondary);cursor:pointer;user-select:none}.range-group{margin-bottom:1.5rem}.range-wrapper{display:flex;align-items:center;gap:1rem}input[type=range]{flex:1;height:6px;background:var(--bg-tertiary);border-radius:3px;outline:0;-webkit-appearance:none;appearance:none}input[type=range]::-webkit-slider-thumb{-webkit-appearance:none;appearance:none;width:18px;height:18px;background:var(--accent-yellow);border-radius:50%;cursor:pointer}input[type=range]::-moz-range-thumb{width:18px;height:18px;background:var(--accent-yellow);border-radius:50%;cursor:pointer;border:none}.range-value{min-width:50px;text-align:center;color:var(--text-primary);font-weight:600;font-size:1.1rem}.display-field{position:relative;margin-bottom:1.5rem}.display-field input{padding-right:100px}.copy-btn{position:absolute;right:8px;top:50%;transform:translateY(-50%);padding:.5rem 1rem;font-size:.9rem}.timezone-list{margin-top:1.5rem}.timezone-item{padding:1rem;background-color:var(--bg-secondary);border:1px solid var(--border-color);border-radius:4px;margin-bottom:.75rem;display:flex;align-items:center;gap:1rem}.timezone-emoji{font-size:1.5rem}.timezone-name{font-weight:600;color:var(--text-primary);min-width:120px}.timezone-time{color:var(--text-secondary);font-family:'Courier New',monospace}@media (max-width:768px){.container{padding:1rem}header{padding:.5rem 1rem}header h1{font-size:1.1rem}.page-title{font-size:1.5rem}.range-wrapper{flex-direction:column;align-items:stretch}.range-value{text-align:left;margin-top:.5rem}.display-field input{padding-right:80px;font-size:.9rem}.copy-btn{padding:.4rem .8rem;font-size:.85rem}.timezone-item{flex-direction:column;align-items:flex-start;gap:.5rem}}@media (max-width:480px){.container{padding:.75rem}.page-title{font-size:1.25rem}input[type=number],input[type=text]{font-size:.9rem;padding:.6rem .8rem}}.text-center{text-align:center}.mt-1{margin-top:.5rem}.mt-2{margin-top:1rem}.mt-3{margin-top:1.5rem}.mb-1{margin-bottom:.5rem}.mb-2{margin-bottom:1rem}.mb-3{margin-bottom:1.5rem}